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Early science with the Expanded Very Large Array C. Carilli and R. Perley (NRAO)

Early science with the Expanded Very Large Array C. Carilli and R. Perley (NRAO). Brief intro: impact and evolution Early science: highlights from the ApJL special issue Broad impact: few examples Molecular gas in early galaxies: tracing fuel for star formation over cosmic time

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Early science with the Expanded Very Large Array C. Carilli and R. Perley (NRAO)

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  1. Early science with the Expanded Very Large Array C. Carilli and R. Perley (NRAO) • Brief intro: impact and evolution • Early science: highlights from the ApJL special issue • Broad impact: few examples • Molecular gas in early galaxies: tracing fuel for star formation over cosmic time • Project description and status

  2. Public and professional impact of astronomical facilities (Courtesy M. Garrett) Peer reviewed papers 2000-2010 VLA Google Hits • VLA: a facility for everyone • VLA receives ~ 500 proposals per year • NRAO PST has 4000 registered users

  3. Problem: VLA is 30yrs old Solution: the Expanded Very Large Array! Build on existing infrastructure, replace all electronics (correlator, Rx, IF, M/C) => multiply ten-fold the VLA’s observational capabilities • 80x Bandwidth (8 GHz, full stokes), with 16384 channels • Full frequency coverage from 1 to 50 GHz • 10x continuum sensitivity (<1uJy) • 40mas resolution at 43GHz (7mm) • Well on way to completion end of 2012 EVLA + ALMA represent > order of magnitude improvement in observational capabilities from 1 GHz to 1 THz

  4. Early science with the EVLA: ApJL special issue • Started in March, 2010, w. up to 2GHz BW • Only compact configurations and (mostly) higher frequencies • Typically broad program: 36 articles spanning A2010 key science panels • The Galactic Neighborhood • Deep radio continuum imaging of the dwarf irregular IC10: tracing star formation and magnetic fields (Heesen) • Complex radio spectral energy distributions in luminous IR galaxies (Leroy) • SHEILD: The survey of HI in extremely low mass dwarfs (Cannon) • EVLA detection of 44.1GHz class I methanol masers in Sgr A (Philstrom) • EVLA observations of Galactic supernova remnants (Bhatnagar) • Discovery of a nearby galaxy discovered in the Arecibo zone of avoidance (McIntyre) • EVLA detection of 44.1GHz class I methanol masers in Sgr A (Philstrom) • Planetary Systems and Star Formation • EVLA observations of the Barnard 5 star forming cloud: embedded filaments revealed (Pineda) • The mm colors of a young binary disk system in the Orion Nebular Cluster (Ricci) • Microwave observations of edge-on protoplanetary disks (Melis) • First results from a 1.3cm EVLA survey of massive protostellar objects (Brogan) • Unveiling the sources of heating in the vicinity of the Orion-KL hot core as traced by High-J rotational transitions of NH3 (Goddi) • EVLA continuum observations of massive protostars (Hofner) • Searching for new hypercompact HII regions (Sanchez) • Stars and Stellar Evolution • Gone with the wind: EVLA observations of the nebula around G79.29+0.46 (Umana) • A pilot imaging line survey of AGB stars RW Lmi and IK Tau (Claussen) • IRAS 18113-2503: the PN water fountain with the fastest jet? (Gomez) • EVLA observations of the classical Nova V1723 Aquilae (Krauss) • A deep radio survey of hard state and quiescent black hole binaries (Miller-Jones) • Auroral emission from stars: the case of CU Virginis (Trigilio) • Galaxies through cosmic time (CO!) • EVLA observations of a proto-cluster of molecular gas rich galaxies at z=4.05 (Carilli ) • CO line emission from z=6 quasar host galaxies (Wang) • Imaging the molecular Einstein ring at z=3.9 (Lestrade) • Extended molecular gas reservoirs in z=3.4 submm galaxies (Riechers) • CO in z = 2 quasar host galaxies: no evidence for extended gas reservoirs (Riechers)

  5. PSSF: subsonic cloud fragmentation in low mass star forming region Bernard 5 Pineda ea 0.5km/s σ< 50 m/s <0.2km/s λJ YSO YSO GBT NH3 EVLA • High spectral/spatial res. imaging of NH3 => densities > 104 cm-3 • GBT: clearly-bounded region of suppressed turbulence in molecular dark cloud: σ falls from 0.5 km/s to < 0.2km/s • EVLA: filament of dense gas, substructures < 1000AU, σ < 50 m/s! • Separation YSO and starless core ~ Jeans length

  6. SSE: 18 to 40 GHz imaging line survey of AGB stars RW LMi HC3N • AGB outflows are key to ISM molecule and dust enrichment (Mass loss rate ~ 10-4 Mo/yr) • Pilot study w. new 36 GHz band: HC3N reveals multiple shells tracing episodic circumstellar envelope evolution, on road to PNe • Shell radii ~ 800 to 4000 AU, vexp ~ 13 km/s => age date outbursts over last 1200 yrs • SiS emission much more compact 8000AU Claussen ea SiS

  7. GN: IC10 = laboratory for studying star formation in dwarf galaxies on 50pc scales radio contours + Hα Heesen ea • EVLA: wide-band allows total intensity + spectral index imaging • 4-8 GHz emission traces Hα closely ~ ½ thermal, ½ synchrotron • SFR (radio/Hα) suggests ~ ½ of CRs lost in outflow • B fields confine cosmic rays in ‘superbubble’

  8. GTCT: molecular gas in early galaxies and the dense gas history of the Universe GN20 z=4 submm galaxy Wilson et al. CO image of ‘Antennae’ merging galaxies CO HST/CO/SUBMM • cm/mm reveal the dust-obscured, earliest, most active phases of star formation in galaxies • cm/mm reveal the cool gas that fuels star formation

  9. cm  submm astronomical probes of galaxy formation 100 Mo yr-1 at z=5 • Low J molecular lines: total gas mass, dynamics • Synch. + Free-Free = star form. (GBT) • High J molecular lines: gas excitation, physical conditions • Dust continuum = star form. • Atomic fine structure lines: ISM gas coolant

  10. Massive galaxy and SMBH formation at z~6: Quasar hosts at tuniv<1Gyr SDSS1148+5251 z=6.42 FIR HyLIRG MBH ~ 109 Mo Wang sample 35 z>5.7 quasars • 30% of z>2 quasars have S250 > 2mJy • LFIR ~ 0.3 to 1.3 x1013 Lo => SFR ~ 103 Mo/yr • Coeval, rapid formation of SMBH and massive host galaxy in early Universe

  11. Molecular gas = fuel for star formation 11 CO detections in z~6 quasars with EVLA, PdBI • M(H2)~ 0.7 to 3 x1010 (X/0.8) Mo • Very early enrichment of dust and metals • Imaging: multiple CO sources => gas rich mergers? EVLA CO 2-1 z=6.2 200uJy z=5.8 1” Wang ea

  12. CO excitation: Dense, warm gas, thermally excited to 6-5 230GHz 691GHz starburst nucleus Milky Way • LVG model => Tk > 50K, nH2 = 2x104 cm-3 • Galactic Molecular Clouds (50pc): nH2~ 102 to 103 cm-3 • GMC star forming cores (~1pc): nH2~ 104 cm-3

  13. LFIR vs L’(CO): Star Formation Law at tuniv < 1Gyr ‘Integrated Kennicutt-Schmidt relation’ • Further circumstantial evidence for star formation • Gas consumption time (Mgas/SFR) decreases with SFR • FIR ~ 1010 Lo/yr => tc > 108yr FIR ~ 1013 Lo/yr => tc < 107yr SFR 1e3 Mo/yr Index=1.5 MW 1e11 Mo Mgas

  14. Imaging => dynamics => weighing the first galaxies z=6.42 0.15” TB ~ 25K Plateau de Bure CO3-2 VLA -150 km/s 7kpc 1” ~ 5.5kpc + +150 km/s Riechers ea • Size ~ 6 kpc, with two peaks ~ 2kpc separation • Dynamical mass (r < 3kpc) ~ 6 x1010 Mo • M(H2)/Mdyn ~ 0.3

  15. Break-down of MBH – Mbulge relation at high z Wang ea • <MBH/Mbulge> ~ 15 higher at z>4 => Black holes form first? • CO/dust imaging is only probe host galaxy to date • Caveats: • Need better CO imaging • Bias for optically selected quasars? MBH = 0.0014 Mbulge => causal connect between BH and gal. formation

  16. z=4: GN20 molecule-rich proto-cluster CO 2-1 in 3 submm galaxies within 30”, 256 MHz 0.7mJy 0.3mJy • 19 z~4 LBGs • 3 SMGs at z ~ 4.05 • LFIR ~ 1013 Lo • SFR ~ 103 Mo/yr • M(H2) ~ 1011 Mo • Clustered, massive galaxy formation at tuniv ~ 1.6Gyr sBzK z=1.5 1000 km/s z=4.055 4.056 0.4mJy 4.051 Daddi ea; Carilli ea

  17. Spectroscopic imaging: A detailed look at massive galaxy formation in the early Universe CO2-1 + 1” 30kpc HST/CO/SUBMM • GN20: Obscured starburst at z=4.0 • Rotating, gravitationally disturbed disk ~ 10 kpc • Mdyn (r<5kpc) ~ 3x1011 Mo ~ Mgas + M* +250 km/s + -250 km/s

  18. ‘Serendipitous’ detection of CO in same field/band from ‘typical’ star forming galaxy at z=1.5 (‘sBzK galaxy’) • SFR ≤ 100 Mo/yr • HST/Hα/CO imaging => ‘clumpy, rotating disk’ ~ 10kpc (Genzel, Tacconi, Daddi) • Systematically detected in CO: Mgas > 1010 Mo=> massive gas reservoir w/o extreme starburst • Good news for EVLA: common ~ 5 arcmin-2 ~ 100x SMGs z=1.5 EVLA CO 1-0 Daddi; Aravena PdBI CO2-1 400 km/s

  19. Closer to Milky Way-type gas conditions LFIR/L’CO HyLIRG 1.5 1 sBzK Dannerbauer, Aravena ea • Lower CO excitation: low J observations are key! • FIR/L’CO: Gas consumption timescales ~ few x108 yrs • => Secular disk galaxy formation during epoch of galaxy assembly

  20. Gas dominated disks Mgas ≥ Mstars => fundamental change in galaxy properties during peak epoch of cosmic star formation (z~2) • EVLA: Large cosmic volume blind searches for molecular gas • 19 to 27 GHz => CO1-0 at z=3.2 to 5.0, 1 beam = 104 cMpc3 • Every few hour EVLA observation at > 20 GHz will discover new galaxies in CO! M* > 1010 Mo sBzK Fgas = MH2/(M*+MH2) BX/BM BX/BM Geach ea.; Daddi ea; Carilli ea.; Tacconi ea.

  21. Dense gas history of the Universe H2 Bouwens ea EVLA is poised to trace the fuel for star formation over cosmic time SF Law [Obreschkow ea; Del P. Lagos ea.; Bauermeister ea; Carilli ea] LIR ~ SFR LCO ~ Mgas

  22. National Radio Astronomy Observatory The Expanded Very Large Array: What It Can Give You, andHow to Get It Rick Perley EVLA Project Scientist National Radio Astronomy Observatory

  23. EVLA Project Overview • The Expanded Very Large Array is a major upgrade of the Very Large Array. • The fundamental goal is to improve all the observational capabilities of the VLA -- except spatial resolution -- by at least an order of magnitude • The project will be completed by the end of 2012 • The EVLA is available now with unprecedented new capabilities.

  24. Key EVLA Capability Goals • Full frequency coverage from 1 to 50 GHz. • Up to 8 GHz instantaneous bandwidth, per polarization • New correlator with 8 GHz/polarization capability • Unprecedented flexibility in matching resources to enable science goals. • Many special modes for special applications. • Full Polarization standard for all correlator setups • <3 mJy/beam (1-s, 1-Hr) continuum sensitivity at most bands. • <1 mJy/beam (1-s, 1-Hr, 1-km/sec) line sensitivity at most bands. • Noise-limited, full-field imaging in all Stokes parameters for most observational fields.

  25. EVLA-VLA Capabilities Comparison The EVLA’s performance will be vastly better than the VLA’s:

  26. EVLA Resolution • EVLA is a reconfigurable array • The resolution, in arcseconds is given in the table: • The largest angular size which can be imaged in any configuration is about 25 times the listed resolution. • If larger-scale structure imaging is required, observations in a smaller configuration are needed.

  27. EVLA Sensitivity (rms in 1 Hour)

  28. EVLA Status • All 28 antennas are now converted to EVLA standards. • Installation of new wideband receivers now complete at: • 4 – 8 GHz (C-Band) • 18 – 27 GHz (K-Band) • 27 – 40 GHz (Ka-Band) • 40 – 50 GHz (Q-Band) • Installation of remaining four bands completed late-2012. • 2 GHz-wide bandwidth available now on all bands. • 8 GHz-wide bandwidth available end of 2012. • Correlator installation (nearly) complete. • Basic (‘continuum’ and spectral survey) modes working well. • Flexible tuning modes nearly ready. • Some special modes (phased array, subarrays) available soon.

  29. Full-Band Receiver Availability Timescale • Four receiver bands are now fully outfitted: C band (4 – 8 GHz), and K, Ka, Q: (18 – 50 GHz). • At 1—2 and 8—12 GHz, all antennas are equipped with a mix of old/new receivers • 2 – 4 and 12 – 18 GHz band receivers are new. • Full-bandwidth availability (8 GHz/pol.) awaiting high-speed sampler installation.

  30. Getting On the EVLA • There are two programs for getting on the EVLA: • OSRO (Open Shared Risk Observing) • RSRO (Resident Shared Risk Observing). • OSRO: • No residency requirement – you can stay home. • Visibility data available from archive via ftp, or by disk shipment. • Maximum bandwidth: 2 GHz (starting Sept 2011) • Configured as two separate tunings, each up to 1 GHz wide. • Eight contiguous subbands within each tuning. • Standard observing mode provides full polarization, with 64 channels per visibility product.

  31. OSRO Spectral Resolutions • There are 13 different subband (spectral window) widths available to OSRO: • All subbands must be adjacent, with same width and channel resolution. • Time resolution: 1 second minimum (default for A-Cfg.) • Doppler setting available for each scan. • Access via existing time allocation process.

  32. RSRO Capabilities • RSRO gives users access to more advanced modes. • Requires extended residency in Socorro • Up to 25% of all observing time available for this pgm. • Major advantage: More spectral resolution: • Next step: flexible tuning of subbands…

  33. Expanding RSRO Capabilities • As commissioning and development proceeds, more complex correlator modes become available, including • Recirculation: doubles spectral resolution for each halving of the subband width (assumed in previous table). • Individual subband tuning: Allows specific targeting of individual spectral transitions. • Individual subband tuning with individual subband widths. • Access to full bandwidth observing: Full 8 GHz bandwidth comes on line in 2012. • Difficult to predict when these enhanced capabilities will be available, but all are under active development now. • RSRO participants expected to assist in EVLA commissioning and development.

  34. Two Routes to RSRO • A: An Accepted Scientific Proposal • At least one ‘expert’ per proposal to assist with commissioning • ‘Black Belt’ status not required • Enthusiasm and willingness to learn is required! • Apply via regular proposal process • Two extra pages justification permitted • Science justification required • Technical section (‘How we can help’) • Budget section (if NRAO support is requested). • One month residency required for each 20 hours of EVLA time. • Minimum of 3 months. • Single visit preferred. • B: Apply to the NM Assistant Director for residency • Justify your technical capabilities and costs. • ‘Time served’ will be credited for future proposals.

  35. Submitting Your EVLA Proposal • Use NRAO’s Proposal Submission Tool • Normal proposals • Semester system • Submission deadlines are August 1 and February 1 • Types are Regular, Large and Triggered • 2011 August 1 deadline: configurations C, CnB and B • 2012 February 1 deadline: configurations BnA and A • At any deadline, requests for future configurations will also be considered • Director’s Discretionary Time proposals • May be submitted 24/7 • Types are Exploratory and Target of Opportunity

  36. EVLA Data Products • Data are in form of visibilities. • No ‘reference images’ available yet. • Data volumes can be large (up to 1 TB). • OSRO data can be collected through the archive (smaller volumes) or sent on external disk. • RSRO data available from archive in Socorro. • OSRO data can be reduced in AIPS or CASA • RSRO data are expected to be reduced in CASA • Many RSRO setups can be calibrated via AIPS. • Remember: The ‘SR’ in OSRO and RSRO stands for ‘Shared Risk’ – no guarantees!

  37. On-Line Help • Virtually all the information (and much much more!) given in this presentation is available online • Start at: https://science.nrao.edu/facilities/evla

  38. Wide-band Galactic Plane Survey: Pilot Project G55.7+3.4 1.2-1.9GHz Res: 30” RMS: 10 uJy/b Spectral Index UC HII Region Flat Spectrum Non-thermal synchrotron Wide-field, wide-band, high dynamic range imaging: simultaneous total intensity and spectral index 2deg

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